caa a22 4500 465809901 CHVBK 20180323112113.0 cr unu---uuuuu 170327e19901001xx s 000 0 eng 10.1007/BF02820570 doi (NATIONALLICENCE)springer-10.1007/BF02820570 Dubniĉka S. INFN, Laboratori Nazionali di Frascati, Frascati (Roma) aut Comment on the prediction of the $$e^ + e^ - \to n\overline n $$ cross-section to be remarkably larger than the $$e^ + e^ - \to p\overline p $$ [Elektronische Daten] [S. Dubniĉka] Summary: The former modified six-resonance VMD model with the correct analytic properties of nucleon electromagnetic form factors and the asymptotic behaviour predicted by the quark model for baryons is improved, first by an addition of the \gr\s's(2150) meson contribution, then taking masses and widths of all considered resonances to be fixed at the world-averaged values and finally, differing also the effective inelastic threshold of the isoscalar (isovector) Dirac nucleon form factor from the effective inelastic threshold of the isoscalar (isovector) Pauli nucleon form factor. By means of the resultant model the analysis of all existing spacelike region nucleon form factor data is repeated. In the timelike region just the attainable data on $$e^ + e^ - \to p\overline p $$ cross-section are employed and the assumption currently used by experimentalists about the equality of electric and magnetic proton form factors close above the proton-antiproton threshold is tested in this manner. The prediction of the $$e^ + e^ - \to n\overline n $$ cross-section to be remarkably larger than the $$e^ + e^ - \to p\overline p $$ one is established again. Società Italiana di Fisica, 1990 Quantum electrodynamics nationallicence Il Nuovo Cimento A (1965-1970) Società Italiana di Fisica 103/10(1990-10-01), 1417-1426 103:10<1417 1990 103 40763 https://doi.org/10.1007/BF02820570 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02820570 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Dubniĉka S. INFN, Laboratori Nazionali di Frascati, Frascati (Roma) aut NATIONALLICENCE 773 0- Il Nuovo Cimento A (1965-1970) Società Italiana di Fisica 103/10(1990-10-01), 1417-1426 103:10<1417 1990 103 40763 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer